Jean Lab

Jean Lab Conclusion

Brandon Yuen

In this lab, we asked, “What concentration of bleach is the best to fade the color out of new denim material in 10 minutes without visible damage to the fabric?” We found that 50% of bleach concentration was the best. It didn’t have much visible damage, and was much lighter than without bleach. The 100% concentration of bleach made the jean square completely white, but it felt flimsy and weak. This happened because bleach is a base, and a base is acidic, so it quickly dissolved bits of the jean square. The 50% concentration of bleach was just right, leaving the jean square strong while still whitening it. The higher the concentration of bleach,  the lighter and weaker it became.

While our hypothesis was supported by our data, there could have been errors. We put the jean squares into the petri dishes one by one, making some of the jeans soak longer. As we took it out, we also took them out one by one, making some squares soak for longer or shorter periods of time. This could have let some jeans get more bleached than others. Also, while measuring water and bleach, we might not have been completely accurate, making the percentage of bleach concentrations go higher or lower. Due to these errors, in future experiments I would recommend having all group members hold the jeans, and put them into the bleach concentration at the exact same time, also when taking them out.

This lab was done to demonstrate the effects of different concentrations of bleach to jeans. From this lab, I learned about the scientific method, which helps me understand the concept of experimenting. Based on my experience from this lab, I know to use a 50% concentration of bleach to slightly whiten jeans, without making them weak. I also know how to set up and do an experiment following the scientific method.

Concentration (% bleach)	Average Color Removal (scale 1-10)	Average Fabric Damage (scale 1-10)
100	8.67	8
50	5.34	4.67
25	2.67	1.67
12.5	1.33	.33
0	0	0